Fourth seed Coco Gauff came from a set and a break down to beat Paula Badosa to reach her first China Open final.
The 20-year-old American dug deep to come through 4-6 6-4 6-2.
Spaniard Badosa, ranked 19th in the world but a former world number two, had looked in a good position when she served at 4-3 up in the second set.
But Gauff broke and rattled off the next four games to set up a decider, eventually wrapping up victory in two hours and 21 minutes.
She will face either unseeded Czech player Karolina Muchova or home favourite and fifth seed Qinwen Zheng in the final.